For what it's worth (I have a 1-ton, not a 1/2-ton -- big difference to the 216) ... I went through a similar decision process and ultimately decided to replace my perfectly fine 216 with a 261 for the following reasons:
1. Peer pressure. Yes, I am man enough to admit it.
2. I like to do a lot of group driving and with the 216, the rest of the gang was having to slow down often to let me catch up (refer to No. 1 above). The 216 with the stock 5.something rear end pretty much limited me to 50 MPH. a little more if I made it scream, which I didn't want to do that much. It also rendered long distance trips out of the question (Interstates were off limits to me). Even after I replaced the third member in the rear axle with a 4.10 gear set, the 216 really ran out of power fast at the top end. It would quickly lose power and speed at even the slightest up grade or head wind.
Speaking of Interstates ... if I want to go anywhere outside of my county (for shows, cruises, get togethers, etc) I pretty much have to deal with the Washington DC beltway. Driving an all original truck on the DC Beltway isn't merely a bad idea, it's just plain stupid. Who doesn't love an all-original truck?? But I like to actually play with my toys (and survive the experience).
3. My regular driving around home puts me in a fair amount of multi-lane, stop and go (traffic lights), and the 216 pretty much made me a traffic obstruction and it seemed that everyone was desperate to drive like idiots to get around me -- not a fun driving experience.
4. If you drive the 216 a lot, you will have to get good at keeping your engine clean (because of all the oil blowing out of the valve cover and road tube) AND you will have to learn how to properly adjust your valves ... you will be doing it a lot to keep the 216 happy.
My decision really came down to deciding what I enjoyed more -- having a really original trailer queen I could only drive around within 25 miles of the house, or having a useful truck I could drive safely and adequately whatever I wanted to do (run a load from the feed mill and not block traffic or cruise 400 miles on the Interstate). I choose the latter.
And also FWIW, my 261 has an 848 head on it. I am also man enough to admit that I do not really know what the 848 head does for my performance actually, but it is fun to hear people say "oooooh, he's got an 848 head on his 261 ..." Of course, that is tempered by the fact that towering over that 848 head is a single Rochester carburetor on a stock intake ... buy hey, it's an 848 head ...
Anyway ... we all love the venerable 216. Truly a remarkable engine. but if you want to really enjoy your truck by driving it ... a lot .... give it a well-deserved retirement to a place of honor in your shop (in the corner ... set some lights on it and decorate the wall behind it with suitable shop art to make a shrine of sorts ...
) and put a more modern engine in your truck.
IMPORTANT NOTE :: IF you decide to replace the engine, PLEASE ... before you go cruising the interstates, be sure to get your front end, steering and brakes in order. Consider installing seat belts (easy to do) and keep in mind that while these old trucks can handle modern highway speeds (once properly set up), they weren't designed for it. You do have to keep that in mind and adjust your driving habits appropriately.